Windows Phone 7.8 will never get another update, other than perhaps bug fixes. Microsoft has determined that devices created prior to Windows Phone 8 being released do not have the features and power necessary to handle the upgrade. Kind of a raw deal for early adopters, but not unprecedented.

unlike PCs OS platform phones are made to have a 2 year life cycle, beyond that they may release patches to fix critical updates for another year or two, but no minor versions will be released. exp after a new platform is on the market.